The run level determines which services will run and which will be stopped during system initialization. The run levels are given below:    0   Halt the system.   1    Single-user mode (for system maintenance).   2    Local Multiuser with Networking but without network service (like NFS)   3    Full Multiuser with Networking   4    Not Used   5    Full Multiuser […]

Continue reading about Changing run levels for Linux/Unix